The ability to increase the storage capacity of magnetic recording media is an on going concern. As the bit areal densities of magnetic recording media continue to progress in an effort to increase the storage capacity of hard disc drives, the physical size of the sensors and writers designed to read and write data from and to the magnetic recording media must correspondingly decrease. As a result of this push to increase the storage capacity of hard disc drives, magnetic transition, i.e., bit, dimensions and, concomitantly, recording head critical features are being pushed below the 100 nm scale. In a parallel effort, in order to make the magnetic recording medium stable at higher areal densities, magnetically harder recording medium materials having a high coercivity are required. The high coercivity of the recording medium helps to ensure the thermal stability of the data recorded thereon. However, a problem with using high coercivity recording media is that the magnetic field from the small recording pole needs to be sufficient to overcome the coercivity of the magnetic recording medium in the disc in order to define the recorded bits along the recording track in the recording medium.
Traditionally, writing to a harder recording medium has been achieved by increasing the saturation magnetic flux density, i.e., 4πMs value, of the magnetic material which makes up the inductive write head, thus bolstering the magnetic field applied to the recording medium. Although there has been some success in the field of materials research to increase the saturation magnetization Ms of write heads, the rate of increase that has been achieved is not significant enough to sustain the annual growth rate of bit areal densities in disc drive storage applications. Further, continued increases in the saturation magnetization of write heads is likely unsustainable as the materials typically used for write heads reach their fundamental limitations.
A consequence of higher areal densities in magnetic recording has been an increase in the data rates at which the data is magnetically recorded. Data rates are advancing toward a point where they will reach a giga-hertz (GHz) and beyond. At these high data rates, it becomes increasingly difficult to switch the magnetization of the recording medium using a conventional write field applied anti-parallel to the magnetization direction of the recording medium, i.e., to the recording medium's easy axis of magnetization. Thus, there is a need in the field of magnetic recording for a recording process capable of switching higher coercivity recording media at increasingly higher data rates.
The present invention is directed toward overcoming one or more of the above-mentioned problems.